The present invention relates to a charged particle beam optical element and a charged particle beam optical system using the element.
The present invention also relates to a charged particle beam exposure apparatus using the charged particle beam optical element and a method of adjusting the apparatus.
Recently, with increasing packing density of semiconductor devices, the circuit patterns of the constituent LSI devices have become finer increasingly. The formation of such fine patterns requires not only small line widths but improvements in the dimensional accuracy and positional accuracy of the patterns.
Many techniques have been developed to meet these demands. Most of these techniques use a method by which a charged particle beam represented by an electron beam is used to directly draw a circuit pattern on a semiconductor substrate, or a charged particle beam represented by an electron beam is used to draw a transfer mask and this mask pattern is transferred onto a semiconductor substrate by using light such as ultraviolet radiation or X-rays or a charged particle beam such as an electron beam or an ion beam. Accordingly, to form fine patterns with high accuracy, it is important to increase the accuracy with which patterns are formed by using a charged particle beam represented by an electron beam.
On the other hand, in addition to an increase in the packing density of semiconductor devices, the device size (so-called chip size) is increasing. Accordingly, a very long time is necessary to draw a circuit pattern of a single LSI device. This leads to a decrease in the throughput, i.e., a decrease in the productivity. Generally, high accuracy and high speed conflict with each other. In particular, the throughput of pattern formation using a charged particle beam is known to be low, although its accuracy is high.